/* This file is part of GNUnet. (C) 2009, 2010 Christian Grothoff (and other contributing authors) GNUnet is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version. GNUnet is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNUnet; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /** * @file mesh/mesh_api.c * @brief mesh service; API for the Mesh. This is used to talk to arbitrary peers * as of 2011-01Jan-06 this is a mockup. * @author Philipp Tölke */ #include #include #include #include #include #include struct tunnel_id { uint32_t id GNUNET_PACKED; struct GNUNET_PeerIdentity initiator; struct GNUNET_PeerIdentity target; }; static uint32_t current_id = 0; struct tunnel_message { struct GNUNET_MessageHeader hdr; struct tunnel_id id; /* followed by another GNUNET_MessageHeader */ }; struct notify_cls { void* notify_cls; GNUNET_CONNECTION_TransmitReadyNotify notify; struct GNUNET_MESH_Tunnel *tunnel; }; struct GNUNET_MESH_Tunnel { /* The other peer this tunnel leads to; just unicast for the moment! */ struct GNUNET_PeerIdentity peer; struct tunnel_id id; /* The handlers and cls for outbound tunnels. Are NULL for inbound tunnels. */ GNUNET_MESH_TunnelDisconnectHandler disconnect_handler; GNUNET_MESH_TunnelConnectHandler connect_handler; void *handler_cls; struct GNUNET_MESH_Handle* handle; /* The application-type requested for this tunnel. Is only needed for pending * by_tupe-tunnels */ uint16_t application_type; /* The context of the receive-function. */ void *ctx; }; struct tunnel_list_element { struct GNUNET_MESH_Tunnel tunnel; struct tunnel_list_element *next, *prev; }; struct tunnel_list { struct tunnel_list_element *head, *tail; }; struct type_list_element { GNUNET_MESH_ApplicationType type; struct type_list_element *next, *prev; }; struct peer_list_element { struct GNUNET_PeerIdentity peer; /* list of application-types */ struct type_list_element *type_head, *type_tail; struct GNUNET_TRANSPORT_ATS_Information atsi; struct peer_list_element *next, *prev; }; struct peer_list { struct peer_list_element *head, *tail; }; struct GNUNET_MESH_Handle { struct GNUNET_CORE_Handle *core; struct GNUNET_MESH_MessageHandler *handlers; struct GNUNET_PeerIdentity myself; unsigned int connected_to_core; struct peer_list connected_peers; struct tunnel_list established_tunnels; struct tunnel_list pending_tunnels; struct tunnel_list pending_by_type_tunnels; void *cls; GNUNET_MESH_TunnelEndHandler *cleaner; size_t hello_message_size; uint16_t *hello_message; }; static void send_end_connect(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tc) { if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) return; struct GNUNET_MESH_Tunnel* tunnel = cls; tunnel->connect_handler(tunnel->handler_cls, NULL, NULL); } static void send_self_connect(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tc) { if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) return; struct GNUNET_MESH_Tunnel* tunnel = cls; tunnel->connect_handler(tunnel->handler_cls, &tunnel->handle->myself, NULL); GNUNET_SCHEDULER_add_now(send_end_connect, tunnel); } static void call_connect_handler (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) return; struct GNUNET_MESH_Tunnel *tunnel = cls; tunnel->connect_handler (tunnel->handler_cls, &tunnel->peer, NULL); GNUNET_SCHEDULER_add_now (send_end_connect, tunnel); } static void core_startup (void *cls, struct GNUNET_CORE_Handle *core __attribute__((unused)), const struct GNUNET_PeerIdentity *my_identity, const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *publicKey __attribute__((unused))) { struct GNUNET_MESH_Handle *handle = cls; memcpy (&handle->myself, my_identity, sizeof (struct GNUNET_PeerIdentity)); handle->connected_to_core = GNUNET_YES; } static size_t send_hello_message (void *cls, size_t size, void *buf) { if (cls == NULL) return 0; GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sending hello\n"); struct GNUNET_MESH_Handle *handle = cls; struct GNUNET_MessageHeader *hdr = buf; size_t sent = sizeof(struct GNUNET_MessageHeader) + handle->hello_message_size; if (sent > size) return 0; hdr->type = htons(GNUNET_MESSAGE_TYPE_MESH_HELLO); hdr->size = htons(size); memcpy(hdr+1, handle->hello_message, handle->hello_message_size); return sent; } /** * Core calls this if we are connected to a new peer. * * The peer is added to the connected_peers-list. * */ static void core_connect (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_TRANSPORT_ATS_Information *atsi) { struct GNUNET_MESH_Handle *handle = cls; GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Core tells us we are connected to peer %s\n", GNUNET_i2s(peer)); /* Send a hello to this peer */ GNUNET_CORE_notify_transmit_ready(handle->core, GNUNET_NO, 42, GNUNET_TIME_UNIT_SECONDS, peer, sizeof(struct GNUNET_MessageHeader) + handle->hello_message_size, &send_hello_message, cls); /* put the new peer into the list of connected peers */ struct peer_list_element *element = GNUNET_malloc (sizeof (struct peer_list_element)); memcpy (&element->peer, peer, sizeof (struct GNUNET_PeerIdentity)); if (NULL != atsi) memcpy (&element->atsi, atsi, sizeof (struct GNUNET_TRANSPORT_ATS_Information)); GNUNET_CONTAINER_DLL_insert_after (handle->connected_peers.head, handle->connected_peers.tail, handle->connected_peers.tail, element); struct tunnel_list_element *tunnel = handle->pending_tunnels.head; while (tunnel != NULL) { if (0 == memcmp (&tunnel->tunnel.peer, peer, sizeof (struct GNUNET_PeerIdentity))) { struct tunnel_list_element *next = tunnel->next; GNUNET_CONTAINER_DLL_remove (handle->pending_tunnels.head, handle->pending_tunnels.tail, tunnel); GNUNET_CONTAINER_DLL_insert_after (handle->established_tunnels.head, handle->established_tunnels.tail, handle->established_tunnels.tail, tunnel); tunnel->tunnel.connect_handler (tunnel->tunnel.handler_cls, peer, atsi); GNUNET_SCHEDULER_add_now(send_end_connect, tunnel); tunnel = next; } else tunnel = tunnel->next; } } /** * Core calls this if we disconnect a peer * * Remove this peer from the list of connected peers * Close all tunnels this peer belongs to */ static void core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer) { struct GNUNET_MESH_Handle *handle = cls; GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Core tells us we are no longer connected to peer %s\n", GNUNET_i2s(peer)); struct peer_list_element *element = handle->connected_peers.head; while (element != NULL) { if (0 == memcmp (&element->peer, peer, sizeof (struct GNUNET_PeerIdentity))) break; element = element->next; } if (element != NULL) { GNUNET_CONTAINER_DLL_remove (handle->connected_peers.head, handle->connected_peers.tail, element); while (element->type_head != NULL) { struct type_list_element* tail = element->type_tail; GNUNET_CONTAINER_DLL_remove(element->type_head, element->type_tail, tail); GNUNET_free(tail); } GNUNET_free (element); } struct tunnel_list_element *telement = handle->established_tunnels.head; while (telement != NULL) { if (0 == memcmp (&telement->tunnel.peer, peer, sizeof (struct GNUNET_PeerIdentity))) { /* disconnect tunnels */ /* outbound tunnels */ if (telement->tunnel.connect_handler != NULL && NULL != telement->tunnel.disconnect_handler) telement->tunnel.disconnect_handler (telement->tunnel.handler_cls, peer); /* inbound tunnels */ else if (NULL != handle->cleaner) handle->cleaner (handle->cls, &telement->tunnel, &telement->tunnel.ctx); struct tunnel_list_element *next = telement->next; GNUNET_CONTAINER_DLL_remove (handle->established_tunnels.head, handle->established_tunnels.tail, telement); GNUNET_free (telement); telement = next; } else { telement = telement->next; } } } /** * Receive a message from core. * This is a hello-message, containing the application-types the other peer can receive */ static int receive_hello (void *cls, const struct GNUNET_PeerIdentity *other, const struct GNUNET_MessageHeader *message, const struct GNUNET_TRANSPORT_ATS_Information *atsi) { struct GNUNET_MESH_Handle *handle = cls; uint16_t *num = (uint16_t *) (message + 1); GNUNET_MESH_ApplicationType *ports = (GNUNET_MESH_ApplicationType*) (num + 1); unsigned int i; GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "The peer %s tells us he supports %d application-types.\n", GNUNET_i2s(other), ntohs(*num)); struct peer_list_element *element = handle->connected_peers.head; while (element != NULL) { if (0 == memcmp (&element->peer, other, sizeof (struct GNUNET_PeerIdentity))) break; element = element->next; } GNUNET_assert(NULL != element); for (i = 0; i < ntohs(*num); i++) { GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "The peer %s newly supports the application-type %d\n", GNUNET_i2s(other), ntohs(ports[i])); if (GNUNET_APPLICATION_TYPE_END == ntohs(ports[i])) continue; struct type_list_element* new_type = GNUNET_malloc(sizeof *new_type); new_type->type = (GNUNET_MESH_ApplicationType)ntohs (ports[i]); GNUNET_CONTAINER_DLL_insert(element->type_head, element->type_tail, new_type); } struct type_list_element *type; for (type = element->type_head; type != NULL; type = type->next) { GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "The peer %s supports the application-type %d\n", GNUNET_i2s(other), type->type); } struct tunnel_list_element *tunnel = handle->pending_by_type_tunnels.head; while (tunnel != NULL) { struct tunnel_list_element *next = tunnel->next; for (i = 0; i < ntohs(*num); i++) { if (ntohs (ports[i]) == tunnel->tunnel.application_type) { GNUNET_CONTAINER_DLL_remove (handle->pending_tunnels.head, handle->pending_tunnels.tail, tunnel); GNUNET_CONTAINER_DLL_insert_after (handle->established_tunnels. head, handle->established_tunnels. tail, handle->established_tunnels. tail, tunnel); tunnel->tunnel.connect_handler (tunnel->tunnel.handler_cls, &tunnel->tunnel.peer, atsi); GNUNET_SCHEDULER_add_now (send_end_connect, tunnel); break; } } if (ntohs (ports[i]) == tunnel->tunnel.application_type) tunnel = next; else tunnel = tunnel->next; } return GNUNET_OK; } /** * Receive a message from core. */ static int core_receive (void *cls, const struct GNUNET_PeerIdentity *other, const struct GNUNET_MessageHeader *message, const struct GNUNET_TRANSPORT_ATS_Information *atsi) { struct GNUNET_MESH_Handle *handle = cls; struct tunnel_message *tmessage = (struct tunnel_message *) message; struct GNUNET_MessageHeader *rmessage = (struct GNUNET_MessageHeader *) (tmessage + 1); struct GNUNET_MESH_MessageHandler *handler; for (handler = handle->handlers; handler->callback != NULL; handler++) { if ( (ntohs (rmessage->type) == handler->type) && ( (handler->expected_size == 0) || (handler->expected_size == ntohs (rmessage->size))) ) { break; } } /* handler->callback handles this message */ /* If no handler was found, drop the message but keep the channel open */ if (handler->callback == NULL) { GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Received message of type %d from peer %s; dropping it.\n", ntohs(rmessage->type), GNUNET_i2s(other)); return GNUNET_OK; } struct tunnel_list_element *tunnel = handle->established_tunnels.head; while (tunnel != NULL) { if (tunnel->tunnel.id.id == tmessage->id.id && (0 == memcmp (&tmessage->id.initiator, &tunnel->tunnel.id.initiator, sizeof (struct GNUNET_PeerIdentity))) && (0 == memcmp (&tmessage->id.target, &tunnel->tunnel.id.target, sizeof (struct GNUNET_PeerIdentity)))) break; tunnel = tunnel->next; } /* if no tunnel was found: create a new inbound tunnel */ if (tunnel == NULL) { GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "New inbound tunnel from peer %s; first message has type %d.\n", GNUNET_i2s(other), ntohs(rmessage->type)); tunnel = GNUNET_malloc (sizeof (struct tunnel_list_element)); tunnel->tunnel.connect_handler = NULL; tunnel->tunnel.disconnect_handler = NULL; tunnel->tunnel.handler_cls = NULL; tunnel->tunnel.ctx = NULL; tunnel->tunnel.handle = handle; memcpy (&tunnel->tunnel.peer, other, sizeof (struct GNUNET_PeerIdentity)); memcpy (&tunnel->tunnel.id, &tmessage->id, sizeof (struct tunnel_id)); GNUNET_CONTAINER_DLL_insert_after (handle->established_tunnels.head, handle->established_tunnels.tail, handle->established_tunnels.tail, tunnel); } else GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Inbound message from peer %s; type %d.\n", GNUNET_i2s(other), ntohs(rmessage->type)); return handler->callback (handle->cls, &tunnel->tunnel, &tunnel->tunnel.ctx, other, rmessage, atsi); } struct GNUNET_MESH_Tunnel * GNUNET_MESH_peer_request_connect_by_type (struct GNUNET_MESH_Handle *handle, struct GNUNET_TIME_Relative timeout, GNUNET_MESH_ApplicationType application_type, GNUNET_MESH_TunnelConnectHandler connect_handler, GNUNET_MESH_TunnelDisconnectHandler disconnect_handler, void *handler_cls) { /* Look in the list of connected peers */ struct peer_list_element *element = handle->connected_peers.head; while (element != NULL) { struct type_list_element* i; for (i = element->type_head; i != NULL; i = i->next) if (application_type == i->type) return GNUNET_MESH_peer_request_connect_all (handle, timeout, 1, &element->peer, connect_handler, disconnect_handler, handler_cls); element = element->next; } GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Trying to connect by tupe %d.\n", application_type); /* Put into pending list */ struct tunnel_list_element *tunnel = GNUNET_malloc (sizeof (struct tunnel_list_element)); tunnel->tunnel.connect_handler = connect_handler; tunnel->tunnel.disconnect_handler = disconnect_handler; tunnel->tunnel.handler_cls = handler_cls; tunnel->tunnel.ctx = NULL; tunnel->tunnel.handle = handle; memcpy (&tunnel->tunnel.id.initiator, &handle->myself, sizeof (struct GNUNET_PeerIdentity)); tunnel->tunnel.id.id = current_id++; tunnel->tunnel.application_type = application_type; GNUNET_CONTAINER_DLL_insert_after (handle->pending_by_type_tunnels.head, handle->pending_by_type_tunnels.tail, handle->pending_by_type_tunnels.tail, tunnel); return &tunnel->tunnel; } struct GNUNET_MESH_Tunnel * GNUNET_MESH_peer_request_connect_all (struct GNUNET_MESH_Handle *handle, struct GNUNET_TIME_Relative timeout, unsigned int num_peers, const struct GNUNET_PeerIdentity *peers, GNUNET_MESH_TunnelConnectHandler connect_handler, GNUNET_MESH_TunnelDisconnectHandler disconnect_handler, void *handler_cls) { if (num_peers != 1) return NULL; struct tunnel_list_element *tunnel = GNUNET_malloc (sizeof (struct tunnel_list_element)); tunnel->tunnel.connect_handler = connect_handler; tunnel->tunnel.disconnect_handler = disconnect_handler; tunnel->tunnel.handler_cls = handler_cls; tunnel->tunnel.ctx = NULL; tunnel->tunnel.handle = handle; memcpy (&tunnel->tunnel.id.initiator, &handle->myself, sizeof (struct GNUNET_PeerIdentity)); memcpy (&tunnel->tunnel.id.target, peers, sizeof (struct GNUNET_PeerIdentity)); tunnel->tunnel.id.id = current_id++; memcpy (&tunnel->tunnel.peer, peers, sizeof(struct GNUNET_PeerIdentity)); struct peer_list_element *element = handle->connected_peers.head; while (element != NULL) { if (0 == memcmp (&element->peer, peers, sizeof (struct GNUNET_PeerIdentity))) break; element = element->next; } if (element != NULL) { /* we are connected to this peer */ GNUNET_CONTAINER_DLL_insert_after (handle->established_tunnels.head, handle->established_tunnels.tail, handle->established_tunnels.tail, tunnel); GNUNET_SCHEDULER_add_now(call_connect_handler, tunnel); } else if (0 == memcmp (peers, &handle->myself, sizeof (struct GNUNET_PeerIdentity))) { /* we are the peer */ GNUNET_CONTAINER_DLL_insert_after (handle->established_tunnels.head, handle->established_tunnels.tail, handle->established_tunnels.tail, tunnel); GNUNET_SCHEDULER_add_now(send_self_connect, tunnel); } else { /* we are not connected to this peer */ GNUNET_CONTAINER_DLL_insert_after (handle->pending_tunnels.head, handle->pending_tunnels.tail, handle->pending_tunnels.tail, tunnel); (void) GNUNET_CORE_peer_request_connect (handle->core, peers, NULL, NULL); } return &tunnel->tunnel; } const struct GNUNET_PeerIdentity* GNUNET_MESH_get_peer(const struct GNUNET_MESH_Tunnel* tunnel) { return &tunnel->peer; } static size_t core_notify(void* cls, size_t size, void* buf) { struct notify_cls *ncls = cls; struct GNUNET_MESH_Tunnel *tunnel = ncls->tunnel; struct tunnel_message* message = buf; void* cbuf = (void*) &message[1]; GNUNET_assert(NULL != ncls->notify); size_t sent = ncls->notify(ncls->notify_cls, size - sizeof(struct tunnel_message), cbuf); GNUNET_free(ncls); if (0 == sent) return 0; sent += sizeof(struct tunnel_message); message->hdr.type = htons(GNUNET_MESSAGE_TYPE_MESH); message->hdr.size = htons(sent); memcpy(&message->id, &tunnel->id, sizeof(struct tunnel_id)); return sent; } /** * Ask the mesh to call "notify" once it is ready to transmit the * given number of bytes to the specified "target". If we are not yet * connected to the specified peer, a call to this function will cause * us to try to establish a connection. * * @param tunnel tunnel to use for transmission * @param cork is corking allowed for this transmission? * @param priority how important is the message? * @param maxdelay how long can the message wait? * @param target destination for the message, NULL for multicast to all tunnel targets * @param notify_size how many bytes of buffer space does notify want? * @param notify function to call when buffer space is available; * will be called with NULL on timeout or if the overall queue * for this peer is larger than queue_size and this is currently * the message with the lowest priority * @param notify_cls closure for notify * @return non-NULL if the notify callback was queued, * NULL if we can not even queue the request (insufficient * memory); if NULL is returned, "notify" will NOT be called. */ struct GNUNET_MESH_TransmitHandle * GNUNET_MESH_notify_transmit_ready (struct GNUNET_MESH_Tunnel *tunnel, int cork, uint32_t priority, struct GNUNET_TIME_Relative maxdelay, const struct GNUNET_PeerIdentity *target __attribute__((unused)), size_t notify_size, GNUNET_CONNECTION_TransmitReadyNotify notify, void *notify_cls) { struct notify_cls *cls = GNUNET_malloc(sizeof(struct notify_cls)); cls->notify_cls = notify_cls; GNUNET_assert(NULL != notify); cls->notify = notify; cls->tunnel = tunnel; GNUNET_CORE_notify_transmit_ready(tunnel->handle->core, cork, priority, maxdelay, &tunnel->peer, notify_size + sizeof(struct tunnel_message), &core_notify, (void*)cls); /* aborting is not implemented yet */ return (struct GNUNET_MESH_TransmitHandle*) 1; } void build_hello_message(struct GNUNET_MESH_Handle* handle, const GNUNET_MESH_ApplicationType *stypes) { int num = 0; const GNUNET_MESH_ApplicationType *t; for (t = stypes; *t != GNUNET_APPLICATION_TYPE_END; t++, num++); GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "I can handle %d app-types.\n", num); handle->hello_message_size = sizeof(uint16_t) + /* For the number of types */ num * sizeof(GNUNET_MESH_ApplicationType); /* For the types */ uint16_t *nums = GNUNET_malloc(handle->hello_message_size); GNUNET_MESH_ApplicationType *types = (GNUNET_MESH_ApplicationType*)(nums + 1); *nums = htons(num); int i; for (i = 0; i < num; i++) { GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "I can handle the app-type %d\n", stypes[i]); types[i] = htons(stypes[i]); } handle->hello_message = nums; } struct GNUNET_MESH_Handle * GNUNET_MESH_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, void *cls, GNUNET_MESH_TunnelEndHandler cleaner, const struct GNUNET_MESH_MessageHandler *handlers, const GNUNET_MESH_ApplicationType *stypes) { struct GNUNET_MESH_Handle *ret = GNUNET_malloc (sizeof (struct GNUNET_MESH_Handle)); ret->connected_to_core = GNUNET_NO; ret->connected_peers.head = NULL; ret->connected_peers.tail = NULL; ret->cleaner = cleaner; ret->cls = cls; const struct GNUNET_MESH_MessageHandler *it; unsigned int len = 1; for (it = handlers; it->callback != NULL; it++) { len++; } ret->handlers = GNUNET_malloc (len * sizeof (struct GNUNET_MESH_MessageHandler)); memset(ret->handlers, 0, len * sizeof(struct GNUNET_MESH_MessageHandler)); memcpy (ret->handlers, handlers, len * sizeof (struct GNUNET_MESH_MessageHandler)); build_hello_message(ret, stypes); static const struct GNUNET_CORE_MessageHandler core_handlers[] = { {&core_receive, GNUNET_MESSAGE_TYPE_MESH, 0}, {&receive_hello, GNUNET_MESSAGE_TYPE_MESH_HELLO, 0}, {NULL, 0, 0} }; ret->core = GNUNET_CORE_connect (cfg, 42, ret, &core_startup, &core_connect, &core_disconnect, NULL, NULL, GNUNET_NO, NULL, GNUNET_NO, core_handlers); return ret; } void GNUNET_MESH_disconnect (struct GNUNET_MESH_Handle *handle) { GNUNET_free (handle->handlers); GNUNET_free (handle->hello_message); GNUNET_CORE_disconnect (handle->core); struct peer_list_element *element = handle->connected_peers.head; while (element != NULL) { struct peer_list_element *next = element->next; while (element->type_head != NULL) { struct type_list_element* tail = element->type_tail; GNUNET_CONTAINER_DLL_remove(element->type_head, element->type_tail, tail); GNUNET_free(tail); } GNUNET_free (element); element = next; } struct tunnel_list_element *tunnel = handle->pending_tunnels.head; while (tunnel != NULL) { struct tunnel_list_element *next = tunnel->next; GNUNET_free (tunnel); tunnel = next; } tunnel = handle->established_tunnels.head;; while (tunnel != NULL) { struct tunnel_list_element *next = tunnel->next; GNUNET_free (tunnel); tunnel = next; } GNUNET_free (handle); } /* end of mesh_api.c */